The Greeks were not only great teachers and artists, they were also the world’s greatest traders and colonizers. 
Jesus said: “The Jews have extolled goodness; the Greeks have exalted beauty; the Hindus preach devotion; the faraway ascetics teach reverence; the Romans demand loyalty; but I require of my disciples life, even a life of loving service for your brothers in the flesh.”.  The backbone of the early Christian church consisted of Christianized Greek proselytes to Judaism.  Greek believers carried Christianity to whole Roman Empire. 
Some Greeks mentioned in The Urantia Book:
The ancient Greeks, having preserved the traditions of Adamson’s teachings, were among the first to recognize that all disease is the result of natural causes.  The early Chinese and the Greeks treated women better than did most surrounding peoples.  Both the Greeks and the Romans favored monogamous marriage. 
The fact of evolution is not a modern discovery; the ancients understood the slow and evolutionary character of human progress. The early Greeks had clear ideas of this despite their proximity to Mesopotamia.  The Greek mind was willing to borrow new and good ideas even from the Jews. 
In Palestine, human thought was so priest-controlled and scripture-directed that philosophy and aesthetics were entirely submerged in religion and morality. In Greece, the almost complete absence of priests and “sacred scriptures” left the human mind free and unfettered, resulting in a startling development in depth of thought. But religion as a personal experience failed to keep pace with the intellectual probings into the nature and reality of the cosmos. In Greece, believing was subordinated to thinking; in Palestine, thinking was held subject to believing. In Palestine, religious dogma became so crystallized as to jeopardize further growth; in Greece, human thought became so abstract that the concept of God resolved itself into a misty vapor of pantheistic speculation. 
Since the Greeks were not much interested in the philosophy of self-realization and an abstract Deity, they turned to mystery cults, such as the Eleusinian mysteries, the Dionysian nature worship, and the Orphic brotherhood. 
No nation ever attained such heights of artistic philosophy in so short a time; none ever created such an advanced system of ethics practically without Deity and entirely devoid of the promise of human salvation; no nation ever plunged so quickly, deeply, and violently into such depths of intellectual stagnation, moral depravity, and spiritual poverty as these same Greek peoples when they flung themselves into the mad whirl of the mystery cults.